MAX1400CAI Maxim Integrated, MAX1400CAI Datasheet
MAX1400CAI
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MAX1400CAI Summary of contents
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... Portable Weigh Scales Loop-Powered Systems Pressure Transducers Ordering Information PART TEMP RANGE MAX1400CAI 0°C to +70°C MAX1400EAI -40°C to +85°C SPI and QSPI are trademarks of Motorola, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’ ...
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... Maximum Current Input into Any Pin ..................................50mA Continuous Power Dissipation (T 28-Pin SSOP (derate 9.52mW/°C above +70°C) ........524mW Operating Temperature Ranges MAX1400CAI .....................................................0°C to +70°C MAX1400EAI...................................................-40°C to +85°C + 0.3V) Storage Temperature Range .............................-60°C to +150°C DD Lead Temperature (soldering, 10s) .................................+300° ...
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Low-Power, Multichannel, ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL OFFSET DAC Offset DAC Range (Note 6) Offset DAC Resolution ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL AIN and REFIN Input Sampling f S ...
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Low-Power, Multichannel, ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL ANALOG POWER-SUPPLY CURRENT (Measured with digital inputs at either DGND ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL 5V POWER DISSIPATION ( ...
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Low-Power, Multichannel, Note 16: Measured the selected passband. PSR at 50Hz will exceed 120dB with filter notches of 25Hz or 50Hz and FAST bit = 0. PSR at 60Hz exceeds 120dB with filter notches of ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC TIMING CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V, AGND = DGND unless otherwise noted.) (Notes 19, 20, 21) PARAMETER SYMBOL SERIAL-INTERFACE WRITE OPERATION SCLK Setup to Falling ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC PIN NAME Clock Input. A crystal can be connected across CLKIN and CLKOUT. Alternatively, drive CLKIN with a 1 CLKIN CMOS-compatible clock at a nominal frequency of 2.4576MHz or 1.024MHz, and leave CLKOUT ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC PIN NAME Negative Gain Calibration Input. Used for system-gain calibration. It forms the negative input of a fully differential input pair with CALGAIN+. Normally these inputs are connected to reference voltages in the ...
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Low-Power, Multichannel, _______________Detailed Description Circuit Description The MAX1400 is a low-power, multichannel, serial- output, sigma-delta ADC designed for applications with a wide dynamic range, such as weigh scales and pres- sure transducers. The functional block diagram in Figure ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Serial Digital Interface The serial digital interface provides access to eight on- chip registers (Figure 3). All serial-interface commands begin with a write to the communications register (COMM). On power-up, system reset, or ...
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Low-Power, Multichannel, Selecting Clock Polarity The serial interface can be operated with the clock idling either high or low. This is compatible with Motorola’s SPI interface operated in (CPOL = 1, CPHA = 1) or (CPOL = 0, ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC FSYNC: (Default = 0) Filter Sync Bit. When FSYNC = 0, conversions are automatically performed at a data rate determined by CLK, FS1, FS0, MF1, and MF0 bits. When FSYNC = 1, the ...
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Low-Power, Multichannel, channels, selection of either calibration mode (01 or 10) will cause the scanning sequence to be extended to include a conversion on both the CALGAIN+/ CALGAIN- input pair and the CALOFF+/CALOFF- input pair. The exact sequence ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 4. SCAN Mode Scanning Sequences (SCAN = 1) DIFF M1 M0 SEQUENCE AIN1–AIN6, AIN2–AIN6, AIN3–AIN6 AIN4–AIN6, AIN5–AIN6 AIN1–AIN6, AIN2–AIN6, AIN3–AIN6 AIN4–AIN6, AIN5–AIN6, CALOFF, CALGAIN AIN1–AIN6, AIN2–AIN6, ...
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Low-Power, Multichannel, Analog Inputs AIN1 to AIN6 Inputs AIN1 and AIN2 map to transfer-function register 1, regardless of scanning mode (SCAN = 1) or single- ended vs. differential (DIFF) modes. Likewise, AIN3 and AIN4 inputs always map to ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 8. Transfer-Function Register Mapping—Normal Mode ( SCAN DIFF ...
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Low-Power, Multichannel, Table 10. Transfer-Function Register Mapping—Gain-Cal Mode ( SCAN DIFF ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 11. Channel ID Tag Codes CID2 CID1 CID0 ...
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Low-Power, Multichannel, External Access to Mux Outputs The MAX1400 provides access to the switching-net- work output and the modulator input with the MUXOUT and ADCIN pins. This allows the user to share a single high-performance amplifier for additional ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 13c Values for Less than 16-Bit Gain Error in Unbuffered (BUFF = 0) EXT EXT Mode—4x Modulator Sampling Frequency (MF1, MF0 = 10 ); X2CLK = 0; f 2.4576MHz ...
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Low-Power, Multichannel, Table 14 Values for Less than 16-Bit Gain Error in Buffered (BUFF = 1) EXT EXT Mode—All Modulator Sampling Frequencies (MF1, MF0 = XX); X2CLK = 0; f 2.4576MHz PGA GAIN C = ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 15. Modulator Operating Frequency, Sampling Frequency, and 16-Bit Data Output Rates MCLK MCLK FREQ. FREQ. X2CLK = 0 X2CLK = 1 DEFAULT f CLKIN f CLKIN (MHz) (MHz) 1.024 2.048 1.024 2.048 ...
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Low-Power, Multichannel, Table 16b. MAX1400 Noise vs. Gain and Output Data Rate—Buffered Mode 2.5V 2.4576MHz REF CLKIN OUTPUT -3dB DATA FREQ. RATE (Hz) (Hz 13.1 6.05 4.13 60 15.7 7.11 4.24 300 ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC The noise shown in Table 16 is composed of device noise and quantization noise. The device noise is relatively low but becomes the limiting noise source for high gain set- tings. The quantization ...
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Low-Power, Multichannel, The on-chip digital filter processes the 1-bit data stream from the modulator using a SINC ter. The SINC filters are conceptually simple, efficient, and extremely flexible, especially where variable reso- lution and data rates are required. ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC input can four times the output data period. For a synchronized step input (using the FSYNC func- tion or the internal scanning logic), the settling time is three-times the output ...
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Low-Power, Multichannel, Figure 13. Example SPI Interface ______________________________________________________________________________________ Oversampling (Sigma-Delta) ADC 29 ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC V DD P3.0 8051 P3.1 Figure 14. MAX1400 to 8051 Interface Figure 15. Bit Banging SPI Replacement 30 ______________________________________________________________________________________ Bit Banging Interface (80C51, PIC16C54) Any microcontroller can use general-purpose I/O pins to interface ...
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Low-Power, Multichannel, Strain Gauge Operation Connect the differential inputs of the MAX1400 to the bridge network of the strain gauge. In Figure 16, the analog positive supply voltage powers the bridge net- work and the MAX1400 along with ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC THERMOCOUPLE R JUNCTION AIN1 SWITCHING NETWORK R AIN2 C C +5V +2.5V REFIN+ REFIN- AGND Figure 17. Thermocouple Application with MAX1400 ISOLATION BARRIER V+ SENSOR 4 4 SPI SPI GND Figure 18. 4–20mA ...
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Low-Power, Multichannel, Grounding and Layout For best performance, use printed circuit boards with separate analog and digital ground planes. Wire-wrap boards are not recommended. Design the printed circuit board so that the analog and digital sections are separated ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 34 © 2002 Maxim Integrated Products ...